(1) Field of the Invention
The present invention relates to a novel and improved structural unit and more particularly to a light-transmissive building element such as a light-transmissive wall element, ceiling element, or roof element, for instance, in the form of windows or the like. Said building element consists of at least two light-transmitting, i.e., transparent panes, panels, or the like which together with frame parts, seals, or the like, define a hollow space in which sound- and heat-insulating means are arranged.
(2) Description of the Prior Art
Despite all endeavors, light-transmissive openings provided with transparent panes, plates, or the like cause even at the present time high heat losses in winter and are also responsible for troublesome, disturbing, and excessive room temperatures in summer. In addition, the continuous noise of traffic on the streets of large cities which detrimentally affects the well-being of the inhabitants, cannot be excluded.
It is known that, partly for architectural reasons and partly for a desire to admit more light, the proportion of light-transmissive outer walls of buildings, auditoriums, and halls and, in part, also of ceiling elements, has increased greatly despite their disadvantages as compared with previous ways of constructing buildings. This development has been aided considerably by the light-weight construction method of building, for instance, skyscrapers. Problems of heat protection and acoustic insulation have been put definitely in the foreground on account of wall elements, particularly of those forming outer walls, which are mounted on building frameworks. In order to overcome thermal disadvantages, air-conditioning of the rooms and highly efficient cooling systems are required, particularly in warmer regions. This requires high expenses which, for instance, in the U.S.A., may at times amount to more than one quarter of the entire costs of the building. Cooling in summer requires about 10 times to 15 times the costs involved for heating a building in winter with respect to the same number of calories. The light-weight construction method naturally lacks the required mass for storing heat. On the other hand, the heat energy produced in the interior of a building in winter flows, due to thermal conduction, practically unimpeded outwardly in the form of infrared rays as a result of the walls transmitting light excessively and of the panes being cooled to the outside temperature. City noises penetrate to an even greater extent through the enlarged light-transmissive walls and windows into residential and business premises and thus complicate all activities.
The wide light-transmissive elements demand a great deal of those building elements which bear and support the front walls.
All this results in serious losses concerning the national economy. Accordingly, an urgent necessity exists to eliminate these thermal and acoustic imperfections by providing novel and particularly combined solutions without doing away with the advantages of the light-weight manner of construction.
In earlier applications directed to light-weight construction elements, solutions have been suggested which make it possible to impart a high amount of thermal and acoustic insulating properties to solid light-impervious structural elements.